Many boards have either WL12XX or MWIFIEX, so let's
build modules for those by default. This also makes it
easier to test WLAN on pandaboard to avoid regressions
like we had with the move to device tree based booting.

And at least the zoom boards need the of_serial for the
UARTs connected to the GPMC bus.
Signed-off-by: Tony Lindgren <tony@atomide.com>